PEOPLE ENJOYS DRINKING COFFEE
TEN BENEFITS OF COFFEE FOR HEALTH, PERFORMANCE & BODY COMPOSITION
At least 5 recent studies show that drinking coffee is associated with a decreased risk of mortality in men and women from a variety of ethnicities. For example, a large-scale 14-year observational study of more than 400,000 people found that the more coffee people drank, the lower their risk of mortality.
Men who drank 2 to 3 cups a day had a 10 percent lower risk of mortality, and those who drank 4 to 5 cups per day had a 12 percent lower risk. Drinking 6 or more cups decreased mortality by another 10 percent compared to non-drinkers. The figures were slightly higher in women, and they remained after adjusting for cofounders like age, body fat, race, education, and lifestyle factors.
Coffee drinking has been associated with a lower risk of lung, prostate, breast, endometrial, pancreatic, stomach, and colon cancer. In some studies the association is robust, while others have shown no benefit from coffee, which could be due to many reasons. But, it seems clear that coffee can be protective and does not increase cancer risk.
It is the antioxidants caffeic and chlorogenic acid that coffee provides that are protective against cancer and other disease. An example of how the antioxidants lower cancer risk is with endometrial cancer, which is a cancer of the lining of the uterus. A study of over 67,000 women demonstrated that women who drank 4 or more cups of coffee per day had a 25 percent lower risk than those who did not drink coffee regularly.
Researchers think the high antioxidant activity in coffee lowered oxidative stress, and that coffee also upregulates the expression of enzymes in the liver that help metabolize estrogen down the healthiest 2-hydroxyestrone pathway. This is a much preferred pathway for detoxifying estrogen from the body and it plays a role in preventing estrogen-related cancers such as breast, ovarian, and prostate cancer in men.
Coffee intake is highly protective for the cardiovascular system and has been repeatedly found to decrease risk of heart disease and death from a heart attack. In one 15-year study of 41,000 women, drinking up to 3 cups of coffee a day was linked to lower risk of heart failure. Similar results have been shown for men.
The caffeine in coffee has actually been shown to improve the health of the blood vessels because it increases nitric oxide production in the endothelium (the thin layer of cells that line the interior surface of blood vessels), which improves vascular muscle tone. Coffee also supports healthy arterial pressure, lowering blood pressure over the long-term.
It is true that drinking caffeinated coffee can increase short-term acute blood pressure, but blood pressure will return to normal once the caffeine is metabolized. One study found that 8 weeks of habitual coffee drinking lowered blood pressure readings significantly.
The antioxidants in coffee can improve total cholesterol, raise “good” HDL cholesterol, and lower inflammation related to heart disease. In one study, regular coffee drinkers were asked to increase their coffee intake to 4 and then a whopping 8 cups a day. This dosing improved the ratio between “bad” LDL and HDL cholesterol by 8 percent.
Metabolic syndrome is the combination of obesity, a large waist circumference, and insulin resistance, all of which increase heart disease and diabetes risk. Coffee drinking can improve fat burning, potentially influencing body composition, and it has been has been closely linked to lower diabetes risk.
For example, one study of a Japanese population showed coffee consumption was inversely correlated with risk of metabolic syndrome because greater intake was associated with lower triglyceride levels and better glucose tolerance.
There is compelling evidence that coffee increases your metabolic rate so that you burn more calories, and it can help shift the body to burn fat rather than glucose for energy. In addition, coffee modulates blood sugar and can improve insulin sensitivity. Caffeine taken alone, however, has been shown to decrease insulin sensitivity, which is only relevant to this discussion if you have problems with insulin, are popping caffeine pills, and eating high-carb foods.
The fat loss effect of coffee drinking hasn’t been studied extensively, but one study showed drinking 500 ml of coffee daily for 4 weeks produced 2.5 kg weight loss in overweight subjects. Perhaps more effective, green coffee extract, which comes from the bean before roasting and can be added to any beverage, has been shown to produce significant fat loss.
One study found that a high-dose of green coffee extract (1050 mg) taken for 6 weeks resulted in an average 8 kg loss in body weight and a 4.4 percent drop in body fat—very impressive! A low green coffee dose produced no changes in body composition.
Sports scientists like to test the effect of caffeine supplements on athletic performance because isolating a part of the plant allows them to avoid confounding variables, such as the antioxidants. That said, you can improve power and strength performance by getting the right dose of pre-workout caffeine from a supplement since using coffee as your sole source of caffeine would require 6 to 9 cups for a 90 kg lifter, depending on sensitivity to the caffeine.
One study found that a dose of 3 mg/kg of body weight of caffeine is necessary to improve power output in the squat and bench press. Another study showed that taking caffeine before early morning workouts can elevate performance in the morning when it is naturally diminished compared to later in the day. Caffeine is thought to act directly on the muscles to produce greater power and strength, rather than acting directly on the nervous system.
Caffeine can speed recovery and reduce post-workout muscle soreness by up to 48 percent. It can also improve performance during a second high-intensity workout performed in one day. One study showed that giving athletes 8 mg/kg of body weight of caffeine after performing a glycogen-depleting exercise trial to exhaustion allowed for better performance on a second sprint interval test also done to exhaustion 4 hours later.
The group that took the caffeine went for 48 minutes compared to only 19 minutes by the placebo group and 32 minutes in a group that only drank carbs. Researchers suggest the caffeine may improve muscle glycogen resynthesize post-workout, while mobilizing fatty acids to be burned for fuel during exercise.
Taking 4 mg/kg of body weight of caffeine improved reaction time on soccer skill tests in athletes when sleep deprived. A similar dose increased motivation and led athletes to voluntarily do more reps using 85 percent of a 1RM load when sleep deprived, resulting in a greater volume compared to a placebo group.
Researchers also measured testosterone and cortisol response to training in this study. The elevations in these hormones correlated to the volume of load lifted, indicating that caffeine did not lead to greater cortisol production. If you are sensitive to caffeine or have issues with cortisol but want the performance benefits of caffeine, take 2 to 10 grams of vitamin C after training. Vitamin C can speed the clearance of cortisol allowing for a better recovery.